1. Field of the Invention
This invention relates to a continuously playable simplified sound reproducing device.
More particularly, this invention relates to a simplified sound reproducing device of the type having a construction comprising: a fixed locking lever disposed on a casing and having a locking face placed parallel to the plane of rotation of the record disc, and a rotating locking lever disposed on the record disc and having a locking face which rotates together with the record disc and proceeds on immediately below the lower face of the locking face of the fixed locking lever only when the record disc is placed in a position retracted from its playing level. At least one of the locking faces is formed with an arc length corresponding to the angle of rotation of the record disc which is sufficient enough to maintain the record disc at its retracted position until the pickup of the device has returned to the starting point of sound reproduction.
2. Description of the Prior Art
Heretofore, there have been provided simplified sound reproducing devices capable of continuously repeating the play of a recorded item.
Such simplified sound reproducing devices function in the following manner, that is; a pickup upon its arrival at the end point of sound reproduction, urges a returning arm which is swingably disposed to engage the pickup at the end point of sound reproduction and make the returning arm ride on an upwardly facing cam, thereby urging a member imparting stylus pressure to the record disc or pickup to move by the stroke of the cam and widens the space between the record disc and the member imparting stylus pressure. This releases the stylus pressure and allows the pickup to return to the end point of sound reproduction (Refer to Japanese Patent Publication No. 45217/81).
The means for actuating return motion of the pickup to continuously repeat sound reproduction, adopted in the prior art device, requires a returning arm; which returning arm is also required to have a return spring having sufficient resiliency. This has brought about disadvantages in saving production costs due to the troublesome and time consuming assembly of a large number of parts.
Above all, the return spring for the returning arm, when it is fabricated with too strong a spring force, is liable to damage the recorded groove through the pickup or introduce such a premature disengagement with the cam means that the pickup returns to the start point of sound reproduction at an undesired stage of playing.
Thus, it has been necessary to arrange some means for adjusting engagement of the cam means with the returning cam.
It was initially conceived to lengthen the top of the cam face in the direction of rotation. However, this inevitably reduces the lower area of the cam face and makes it difficult to set the timing of the return motion of the pickup with respect to the lower area of the cam face.
The present invention aims to solve the drawbacks found in similar prior art devices.
Accordingly, an object of the present invention is to provide a means for returning the pickup which is of simplified construction and which does not rely on a returning arm and a return spring.
Another object of this invention is to provide a means for returning the pickup which can securedly maintain the record disc free from stylus pressure until the pickup has returned to the starting point of sound reproduction. A further object of the present invention is to provide a simplified sound reproducing device capable of continuously repeating sound reproduction which can be readily manufactured and assembled.
A still further object of the invention is to provide a continuous repeating type sound reproducing device which can be manufactured at a low cost.